The TSA, or Transportation Security Administration, oversees airplane security in the United States by checking passengers and their luggage before they reach the plane. At the airport, a TSA agent will confirm your identity as part of the security process. You can use several different forms of photo ID, depending on whether you’ll be traveling on an international or domestic flight and whether you are over the age of 18.

Flying Internationally

A valid passport book is the only acceptable form of ID for passengers boarding international flights. Although you can use a passport card to cross a land border into Canada, Mexico and most of the Caribbean, the card is not valid for any air travel. The TSA accepts your passport as ID at any time before it expires, but some foreign countries impose a minimum length of validity. For this reason, the U.S. Department of State recommends renewing your passport within nine months of its expiration date.

Adults Flying Domestically

If you are over age 18 and taking a domestic flight, the list of acceptable federal- or state-issued ID is much longer. In addition to a passport book or card, TSA staff accepts military IDs, a driver’s license, a border crossing card, a permanent-resident card, Native American tribal photo ID and “Trusted Traveler” cards, such as NEXUS and SENTRI, issued by the Department of Homeland Security. You can also use certain foreign-issued photo ID, including a Canadian driver’s license, an Indian and Northern Affairs Canada card, or a valid passport issued by any foreign country.

Children’s Identification

Children under the age of 18 don’t need any form of ID to board a domestic flight. TSA staff allow children through security so long as they hold a boarding pass issued by the airline they’re traveling with. For international flights, any minor child -- even an infant -- must travel with their own valid passport.

If You Don’t Have Identification

If you forget your ID or lose it on the way to the airport to take a domestic flight, you may still be permitted to board the flight. If you are prepared to provide some information about yourself to TSA staff, they can check it against public databases to confirm your identity. This process is likely to take longer to complete than a straightforward ID check, so ensure you allow extra time to go through security screening and reach the boarding gate.

About the Author

Rita Kennedy is a writer and researcher based in the United Kingdom. She began writing in 2002 and her work has appeared in several academic journals including "Memory Studies," the "Journal of Historical Geography" and the "Local Historian." She holds a Ph.D. in history and an honours degree in geography from the University of Ulster.